I just found some info in Kathy Smith/Lucille Moore's book 'When Your Rabbit needs Special care.
I will quote from the book as I have no personal experience using herbs as treatment and have no idea whether this is accurate info although most of the info in her books is accurate and she is a reliable source on rabbit care and medicine.
"GI System Support"
"Herbs can be useful in preventing digestive upset and in treating early signs of discomfort from minor gas attacks. The herbs discussed in this section should NOT be substituted for a vet visit in cases of GI upset that are severe, appear to be worsening , or last more than a few hours without significant improvement.
The following herbs may help maintain or restore GI health
Fennel: reduces gas and may help appetite
Ginger:improves digestion
Papaya
fresh or dried without added sugar) stimulates appetite and aids digestion. Carefully check the label on papaya tablets. The main ingredient in many brands is sugar and not papaya.
Parsley: relieves gas and stimulates normal GI activity. It is easy to find it in most grocery stores and most rabbits enjoy it.
Peppermint : helps relieve gas and is a digestive aid. Note: Peppermint may counteract the effects of some homeopathic remedies.
Spearmint: relieces gas and colic . It is similarto peppermint butismilder. Some rabbits who don't like peppermint may enjoy spearmint
Thyme:elimintes gas and helps expel some intestinal parasites.
Pg 354-355 "When Your rabbit needs Special care"
Hope this helps your little cottontail James.
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